3.24.53.3 functions

Use ‘set palette functions <Rexpr>, <Gexpr>, <Bexpr>‘ to define three formulae for the R(gray), G(gray) and B(gray) mapping. The three formulae may depend on the variable ‘gray‘ which will take values in [0,1] and should also produce values in [0,1]. Please note that <Rexpr> might be a formula for the H-value if HSV color space has been chosen (same for all other formulae and color spaces).

Examples:

To produce a full color palette use:

      set palette model HSV functions gray, 1, 1

A nice black to gold palette:

      set palette model XYZ functions gray**0.35, gray**0.5, gray**0.8

A gamma-corrected black and white palette

      gamma = 2.2
      color(gray) = gray**(1./gamma)
      set palette model RGB functions color(gray), color(gray), color(gray)